Fixing up under body surface rust and Whiteline ARB's

I had a quick look under the car today while checking something and noticed a bit of light surface rust, mainly around the rear suspension and sub frame section that i would like to clean up and protect. Whats the best way to deal with this?

Also i noticed on my whiteline sway bars, only about 2 years old are starting to rust up and peel around the arb mount brackets. Any DIY solution to re-paint these or is it best to get them powder coated?

Clean down rust as best u can sand paper and what ever u have at your disposal wire brush ect. Sand blaster is king. Clean it with pre clean after. Lash on red oxide primer. U can use a brush. If ur fussy u can put a two pack primer on over the red oxide when it drys. Then paint it with a solid colour using hardener when thats dry. Shulse it after or wax oil or both. Sounds extrem but should do the job. Do it in a dry shed

Whiteline stuff had a sh*t finish super for over in oz but crap here is strip them and powder coat them
they have since changed there paint so it's not an issue nowadays

That's the thing I thought they changed their paint before I bought them. I must check when I bought them.

Could have been old stock